Trainer aircraft



FIG. 1 is a side elevational view of the trainer aircraft, which is the object of the present design, with the opposite side being a mirror image thereof;

FIG. 2 is a bottom plan view thereof;

FIG. 3 is a top plan view thereof;

FIG. 4 is a front elevational view thereof; and,

FIG. 5 is a rear elevational view thereof. 

The ornamental design for a trainer aircraft, as shown and described. 